Hi, you can go back to shanghai and take a train from shanghai to yichang, or you can take a train to wuxi from suzhou first and then take a train at wuxi to yichang. Both will cost you about 24 hours. If you want to travel by air, you should also go to wuxi or shanghai. Actually, i think you should backpack to shanghai as the transportation is more convinient. If you are tight in time. you can go there by air. There are discount, but you need to book as soon as possible. Or it will become more and more expensive. You can also book through this website, it offers good discount.